Duplex window operating device



March 9, 1937. E. .1. KIRCHOFF DUPLEX WINDOW OPERATING DEVICE Filed Mm 5, 1954 4 Sheets-She 'b 1 INVENTOR.

fiaw

fi -i kkm ATTORNEY.

4 Sheets-Sheet 2 E. J. KIRCHOFF DUPLEXWINDOW OPERATING DEVICE Filed Ma rch 5, 1934 March 9, 1937.

March 9, 1937. E. J. KIRCHOFF DUPLEX WINDOW OPERATING DEVICE [F led March 5, 1934 I 4 Sheets-Sheet s March 9,- 'I937.-

mxmxm:

E. J. KIRCHOl-F DUPLEX WINDOW OPERATING DEVICE Filed March 5, 1934 4 Sheets-sheet 4 ATTORNEY.

Patented Mar. 9, 1937 UNITED STATES PATENT OFFICE.

12 Claims.

The object of my invention is to produce a compound window operating mechanism, especially adapted for automobile bodies, for operating pivoted window panels, both vertically and laterally, so as to function the window as a ventilating as well as a closing unit.

Another object is to produce a window operating device, suitable for pivoted window panels, that will function continuously for both vertical and lateral movements of the window panel, through mechanical means actuated by a single crank member and without change in its direction of rotation.

A further object is to provide duplex operating mechanism for pivoted window panels, that will automatically function to rotate the pivoted panel either for opening or closing, only in the extreme raised position of the window within the automobile body frame, and of a structure that may be adapted to any form of pivoted window panel, either of the single or split panel type.

A still further object is to produce a duplex window operating device that is simple in construction, easily and emciently operated and that can be manufactured at a very low cost.

These several objects are attained in the preferred form by the construction and arrangement of parts more fully hereinafter set forth.

Similar parts on all drawings are marked by similar numerals or letters.

Fig. 1 is an inside view of an automobile door, illustrating the preferred type of duplex operating mechanism for the pivoted window panel, showing its adaptability to the split window structure;

Fig. 2 is a vertical sectional view through the door body, taken on the line 2-2 of the Fig. 1, showing the general arrangement of the various operating parts, and the means for mounting same.

Fig. 3 is another vertical sectional view inside the door wall, taken on the line 3-3 of Fig. 2, showing the special gear arrangement of the window lift mechanism.

Fig. 4 is also a vertical sectional view taken on the line 4-4 of the Fig. 2, showing the pivoted window panel rotating shaft and gear, and adjustable means thereunder.

Fig. 5 is a cross sectional view through the split window pane, taken on the line 55 of the Fig. 1, showing the slide arrangement for both movable panels.

Fig. 6 is an inside view of an automobile body door, showing a modified form of the window lifting mechanism, applying a rach and gear structure in the place of the worm type previously shown.

Fig. 7 is a vertical sectional view through the door structure, taken on the line |--'l of the Fig. 6, showing the new arrangement of the lifting gears, and the panel rotating mechanism,

Fig. 8 is a cross section through the door taken on the line 8-8 of the Fig. 6, showing the arrangement of the lifting mechanism.

Fig. 9 is a vertical sectional view inside the door wall, taken on the line 9-9 of the Fig. 7, showing the relative position of the operating gears.

Fig. 10 is the inside view of an automobile door showing a further modified form of lifting mechanism, applying a combination of bevel and spur gears instead of the spiral arrangement shown in the Figs. 1 and 2.

Fig. 11 is a vertical sectional view through the door, taken on the line Il-H of the Fig. 10, showing the arrangement of the bevel power and drive gears, and the operating gears for the pivoted pane.

Fig. 12 is a cross sectional view taken on the line 12-42 of the Fig. 10 showing the relative position of the operating parts.

Fig. 13 is a vertical front view of the lifting mechanism taken on the line I3-l3 of the Fig. 11, showing the wall mountings for the lifting gear shaft.

Fig. 14 is another view of the inside of an automobile door showing a modified arrangement of spur gear lifting mechanism.

Fig. 15 is a vertical sectional view through the door taken on the line l5-l5 of the Fig. 14 showing the spur power gear and latch means for connecting same.

Fig. 16 is a cross sectional view taken on the line Iii-l6 of the Fig. 14 showing the relative position of spur lifting gears and operating mechanism.

Fig. 17 is a cross sectional view taken on the line l1l1 of the Fig. 15 showing the gear arrangement and means for applying a counter weight spring to the lifting mechanism.

It is to be understood that while I have illustrated my device as applied to automobile body windows, that it is equally as well adapted to other types of vehicles such as in aeroplane cabins or railway coaches.

My device is especially adapted to the sliding type of window sash having a movable pane pivot'ally mounted therein, and in general comprises a lifting mechanism and a rotating mechanism, preferable of the shaft and gear type, both actuated by a single operating crank through gear connections, one set of geared mechanismengaging with the crank automatically as the other mechanism is dis-engaged, making the lifting and the rotating operations of the window pane, continuous in both directions, the rotating of the pivoted pane taking place only when the window panel is in. its extreme raised or closed position.

I will now describe more fully the detailed construction of my device, referring to the draw ings and the marks thereon.

The preferred form of window operating mechanism is shown in the Figs. 1. to 5 of the drawings, and is herein applied to an automobile door Window of the split type, designed to raise or lower either glass section, the front section having the pivoted pane, being the portion to which my window operating mechanism is adapted, designed to raise or lower the panel section within the window frame slides, and to rotate the pivoted panel outward when at its extreme top or closed position within the slides.

The window panel I may be made of any suitable material, preferably of some light, strong metal, and formed with the frame rim a and the frame base 12, both positioned in the same plane andprovided with'parallel side slides c and 01 along opposite edges thereof, suitable for engaging with and sliding in either flanged or plain frame slide grooves e and f of an automobile body door A, and as may be required for the special Window frame structure. The rim a is formed to fit the window opening design with which it is to be used, and with the center opening 2 of the same size and shape of the automobile body window opening, positioned to coincide therewith when the window panel I is raised to its closed position, as is illustrated in the Fig. l of the drawings. The frame base b' is preferably rectangular in form and is an extension of the bottom rim and wall slides, the entire panel I being uniform in thickness throughout. Within the center opening 2 of the panel I, is mounted a glass window pane 3, pivotally mounted near the forward edge thereof, by the pivot 4 and the pivot shaft 5 which are securely attached to the pane 3 by edge groove clamps 6 and. I, said pivot members being positioned in parallel alignment capable of allowing the pane 3 to be rotated outward from its closed position, as indicated by the dotted lines 3' in the Fig. 2. The pivot shaft 5 is extended vertically through the frame base b to a position near the bottom thereof, and carries an operating gear 8 mounted thereon, but attached to the pivot shaft 5 with a slight sidewise key adjustment, the bottom of said gear engaging a spring adjusted corrugated retarding collar 9 designed to prevent free rotation or turning of the pivoted pane '3 when dis-engaged from the operating mechanism. Mounted on the inside wall of the door A, is a worm lifting shaft I I], rotatably mounted in the end bearings II and I2 which are fixedly attached to the door wall g, said shaft being shouldered and provided with a helical groove thread h of course pitch, and extending the entire length of the shouldered section. The shaft II! is positioned parallel with the Window frame side slides e and f, and at the upper end thereof carries fixedly mounted thereon a spiral drive gear I3. A threaded worm thimble I4 is threadedly mounted over the worm shaft I0, having like helical internally formed threads therein, suitable for engaging and fitting the helical shaft threads h, and moving the entire length of the shaft II] as said shaft is rotated, the worm thimble I4 being rigidly connected to the bottom edge of the window panel base I), by any suitable means such as the bolts I5, or it may be made as an integral part thereof, and functions to raise or lower the panel I within the supporting window frame slides e and 1. Through the top shaft bearing II, at right angles to the shaft I0, is rotatably mounted a crank shaft I6, and is provided with a suitable crank IIfixedly mounted thereon but positioned on the outside of the door wall 9, T

crank shaft I6 carries fixedly mounted thereon a spiral power gear I8 of like structure and pitch as the drive gear I3 and is positioned to mesh therewith, causing a rotation of the lifting shaft I0 as the crank I! is turned in either direction, for lowering the worm thimble I4 and connected window panel I to the extreme bottom position orraise it to its extreme upper position where said worm thimble I4 passes off the threaded shaft section and rests on the shouldered shaft section lc, allowing further free turning of the shaft I0 in the direction of the raising rotation, but engages the helical shaft thread It upon the reverse rotation of the shaft, assisted by the advanced tooth end m of the thimble and the coil spring n mounted thereabove, and causing the panel I again to be lowered. On the inner end of the crank shaft I6 is fixedly mounted a bevel operating gear I9 of like pitch as the operating gear 8, said operating gears being positioned in parallel vertical alignment, suitable for meshing. and engaging operatively with each other When: the panel I is raised to its extreme closed position, as indicated in Figs. 1 and 2 of the drawings, the slight sidewise key adjustment of the gear 8 on its supporting pivot shaft 5 allowing the said operating gears to readily mesh together even though the respective gear teeth may slightly mismatch. The continued turning of the crank I! in the direction of the raising rotations, will then automatically rotate the pivoted pane 3 on its pivot supports 4 and 5 to an angular position outside the window wall. If the degree of rotation of the shaft 5 is slight, a double helical thread h may be used on the shaft I0 if desired, but should the degree of rotation of the pane 3 be great, the single helical thread would be preferable, as in no case should the lifting shaft I!) be rotated in the raising direction after dis-engaging the thimble I4, so as to allow the helical thread opening to pass the thimble tooth m, unless provided with some proper holding latch, or any reverse rotation of the shaft III will immediately engage the thimble thread and lower the panel I before the pane 3 is completely returned to its 7 closing position therein. On reverse rotation of the crank II, the pane 3 is rotated to its closing position in the panel I as the helical thread h of shaft I0 engages the threaded thimble I4, and automatically lowers the said panel I therewith, said vertical movement dis-engaging the operating gears 8 and I9 as heretofore described. The direction of rotation may be changed in the operating mechanism by the use of either right or left hand spiral gears I3 and I8, or reversing the sides of contact therebetween, or by the use of either right or left hand helical shaft threads h with thimble I4. The possible reverse movement of the operating mechanism allows the device to be readily adapted to any window position, on either side thereof, and always capable of rotating the pivoted window pane 3 in the chosen direction.

The Figs. 6 to 9 illustrate a modified form of lifting mechanism, utilizing a spur gear and rack structure in the place of the worm lifting shaft and thimble I0 and I4. The thimble I4 and the helical shaft threads h are omitted, and the previously described lifting shaft II! is changed to a horizontal position at right angles to the panel slide edges 0 and d, and as is illustrated in the Fig. 6, said shaft Illa being rotatably mounted on the inner face g of the automobile body door Aa, by the newly positioned bearing IZa, and carries a lifting spur gear 20 fixedly mounted on the CPI outer end thereof, said spur gear 20 meshing with a corresponding lifting gear rack 21: onthe adjacent face of the panel edge do. The rack 2| may be either fixedly attached to the panel frame surface by any suitable means, or the rack teeth formed directly into the frame surface metal as illustrated in the drawings. A spiral drive'gear I3 is fixedly mounted on the inner end of the shaft Illa, and meshes with: a like spiral power gear lBa mounted on the crank shaft as in the former case. The direction of rotation of the lifting shaft Illa may be pre-determined by proper selection of the spiral gears l'3' or l8a, or by changing the position of the drive gear li3 to the opposite side of the power gear I'Ba, above or below, but herein illustrated as above. A modification of the crank I! previously shown is required, as the power gear [8a is loosely mounted on the crank shaft [6a and connected thereto by means of a spring latch 22 pivotally mounted in the shaft groove ,1) and which engages a groove recess s formed in the gearbearing of l8a during the driving operation of the shaft Illa. The crank Fla is formed of a hub section 1. fixedly mounted on the outer shaft end, and carries a crank arm w hingedly connected to the hub section, said crank arm 10 being formed with an extended inner cam end a: positioned to engage and lift the spring latch 22 when the arm 10 is pulled out slightly from the automobile door wall, thus dis-engaging the latch 22 from the power gear 18a when the window panel I has reached its extreme closed position, and closing the operating gears 8 and I9 as in the former cases, allowing a continued rotation of the crank Ila for turning the pivoted panel 3 to the desired position. The latch 22 beingdisplaced by the spring member 23 engaging therewith, also reacts to return the crank arm 10 to its raising position when the crank is released, and the latch 22 again engaged the power gear recess s when rotated to that point. The remainder of the device and its operation are exactly the same as described for the previous figures.

Figs. 10 to 13 show a further modification of the drive and power gear mechanism, substituting bevel drive and power gears 13b and lb in the place of the spiral gears l3 and |8a as described for the Figs. 6 to 9; the remaining parts of its structure and its operation are exactly the same as described for the Figs. 6 to 9. However, the direction of rotation of the lifting shaft Hlb cannot be changed or reversed with this type of gear as in the previously described structures, and this device is adapted only to windows when mounted with the lifting rack and gear positioned at th forward window edge, inasmuch as any reverse position of this mechanism would rotate the pivoted panel 3 inside the automobile body instead of outward as required for the proper ventilation.

The Figs. 14 to 1'7 inclusively, show a further modification of the type last previously described in the Figs. 10 to 13, replacing the lifting shaft lllb, the drive and power gears 13b and [8b, with a power spur gear I and the intervening idler gears 24 and 25 for connecting the driving mechanism with the lifting gear 200, and which gear engages a gear rack 2lc attached to the edge of the window panel I, said rack being attached to the panel surface edgewise so as to mesh with the chain of spur gears. The power gear I80 is loosely mounted on the crank shaft l6b and connected therewith by the latch 22 as in the former case. The remaining structure and its operation is exactly the same as for the last previously described units in Figs. 10 to 13'. This device, also like the'previous device, is not reversible in directional rotation of the lifting gear 200, and is adapted to window installation only when applied with the lifting rack and gear positioned at the rear edge of thlewlndow panel, as illustrated in the Fig. 14, in order that thepivoted pane 3 rotate outward. The idler gear 24 affords means for mounting. a spiral counterweight spring 26 thereon, with its respective ends connected to the said gear and door wall, to react and partially carry the panel weight, making the operation easier.

It is to be understoodthat certain modifications in both detail and design may be made herein and without departing from the spirit of my invention, and I claim the designs herein shown and any modification thereof that is substantially a substitution of parts herein shown.

Having fully described my duplex window op erating device, what I claim as my invention and desire to secure by Letters Patent is:

1. A window operating device adapted for producing vertical and lateral adjustment of a pivoted window pane within a supporting window panel frame and used in combination therewith, said window panel frame being slidably mounted within supporting window frame slides, comprising pivot and pivot shaft means for pivotally mounting said window pane within the panel frame opening, said pivot shaft having an auxiliary operating gear mounted therein, a rotatable power unit mounted on the window frame adjacent the panel section, said power unit having means for causing rotations of its operating units, lifting operating mechanism actuated by said rotatable power unit mounted on the window frame and connected operatively with the window panel in a manner for raising and lowering same within the window slides, an operating gear mounted on the power unit positioned to engage operatively with the auxiliary operating gear of the pane pivot shaft when the window panel is in its extreme raised position.

2. A window operating, device adapted for producing vertical and lateral adjustment of a pivotally mounted window pane within a supporting window panel frame and used in combination therewith, said window panel frame being slidably mounted within suitable supporting window frame slides, comprising pivot and pivot shaft means for pivotally mounting said window pane within said panel frame opening, said pivot shaft having an auxiliary operating gear mounted thereon, a shaft retarding unit mounted on said window pane-l engaging said pivot shaft op'era tively to prevent free rotations thereof, a manually operated power shaft and gear rotatably mounted on the supporting window frame, panel slide operating mechanism mounted thereon and connected to the window panel and actuated by the power shaft and gear, in a manner for raising and lowering said panel within the window frame slides as the power shaft is rotated, an opera-ting gear mounted on said power shaft positioned to engage and mesh operatively with the auxiliary operating gear of the pane pivot shaft when the window panel is raised to its extreme closed position.

3. A duplex window operating device adapted for producing vertical and lateral movement of a pivotally mounted window pane within a supporting window panel frame and used in combination therewith, said window panel frame section being slidably mounted within suitable window frame slides, said pivot and pivot shaft means for pivotally mounting said window pane within the window panel frame opening, said pivot shaft having an auxiliary operating gear with shaft retarding means mounted thereon, a power shaft and gear having a manual operating crank, mounted on the supporting window frame, geared panel raising mechanism mounted thereon, connected to and actuated by the power shaft gear, said raising mechanism also being connected with the window panel in a manner for raising and lowering same within the supporting window slides as the power shaft is rotated, an operating gear mounted on the power shaft positioned to engage and mesh operatively with the-auxiliary operating gear of the window pane pivot shaft when the panel is raised to its extreme closed position in the window frame, and means formed thereon for disconnecting the panel raising mechanism from the power shaft as the pane operating gears are closed operatively together.

4. A window operating device adapted for producing vertical and lateral adjustments of a pivotally mounted window pane within a supporting window panel frame and used in combination therewith, said window panel frame section slidably mounted within suitable window frame slides, comprising pivot and pivot shaft means for pivotally mounting said win-dow pane within the window panel frame opening, said pivot shaft having an auxiliary operating gear with spring actuated shaft retarding collar mounted thereon, a power shaft with power gear mounted thereon rotatably mounted within the window frame, said power shaft having an operating crank on one end thereof, a lifting mechanism drive shaft with drive gear attached rotatably mounted on the window frame and positioned with the shaft drive gear meshing operatively with the power shaft gear, panel lifting means mounted on the window panel frame and engaged operatively with said lifting mechanism drive shaft in a manner capable of raising and lowering said window panel within the window frame slides as the power shaft is rotated, said mechanism being formed to become disengaged from the power shaft when said window panel is raised to its closed position, an operating gear mounted on said power shaft positioned to engage and mesh operatively with the window pane pivot shaft auxiliary operating gear when said panel is raised to its extreme closed position and as said lifting mechanism is disconnected from the power shaft.

5. A duplex window operating device adapted for producing vertical and lateral adjustment of a pivotally mounted window pane within a supporting window panel frame and used in combination therewith, said window panel frame being slidably mounted within suitable slide supports within a window frame, comprising pivot and pivot shaft means for pivotally mounting said window pane within the window panel frame opening, said pivot shaft having an auxiliary operating bevel gear and shaft retarding unit mounted thereon, a power shaft with spiral power gear rotatably mounted on the window frame, said shaft having a hand turning crank thereon, a worm lifting shaft with spiral drive gear attached rotatably mounted on the window frame and positioned parallel to the frame panel slides and with the spiral drive gear meshing operatively with the spiral power gear of the power shaft, a worm operating thimble threadedly mounted on the worm lifting shaft and connected to the window panel capable of raising and lowering same therewith, said worm shaft being shouldered beneath the threads at the top end for disengaging the worm shaft threads from the worm operating thimble whenthe panel is raised to its extreme closed position allowing the worm shaft to rotate freely, said worm thimble being formed with a thread. engaging end for reengaging the lifting shaft worm thread on reverse rotation of said shaft, and an operating bevel gear mounted on the power shaft positioned to engage and mesh operatively with the bevel auxiliary gear of the pane pivot shaft when the window panel is in its raised closed position.

6. A window operating device adapted for raising and rotating a pivotally mounted window pane within a supporting window frame and used in combination therewith, window panel frame section being slidably mounted within a window frame, a free window pane comprising pivot and pivot shaft means for pivotally mounting said window pane within the panel frame opening, said pivot shaft having an auxiliary operating bevel gear and a spring actuated shaft retarding unit mounted thereon, a grooved power shaft having a gear latch therein, rotatably mounted in the window frame adjacent the panel, a latch grooved power gear mounted on the power shaft capable of engaging therewith through the shaft gear latch, a lifting mechanism shaft with drive gear attached rotatably mounted on the window frame and positioned at right angles to the window panel slides and with the spiral drive gear meshing operatively with the spiral power gear on the power shaft, a lifting gear rack mounted on the window panel edge, said lifting shaft having a spur lifting gear mounted thereon positioned to engage operatively with the panel gear rack capable of raising and lowering said panel within the window slides as the shaft is rotated, an operating bevel gear mounted on the power shaft positioned to engage operatively with the pane pivot shaft auxiliary operating bevel gear when the window panel is raised to its closed position, a hand operating crank with hinged arm and cam mounted on the outer end of the power shaft, said crank arm cam being positioned to engage the power shaft gear latch for disengaging same from the power gear when the hinged crank arm is disploced on its hinge sup port.

'7. A duplex window operating device adapted for producing vertical and lateral movements of a pivotally mounted window pane within a supporting window frame and used in combination therewith,' window panel frame being slidably mounted within suitable slides formed in a window frame wall, a free window pane comprising pivot and pivot shaft means for pivotally mounting said window pane within the window panel opening, said pivot shaft having an auxiliary operating gear and shaft retarding unit mounted thereon, a grooved power shaft having a spring gear latch therein, rotatably mounted in the window frame, a latch grooved spur power gear mounted on the power shaft and capable of engaging therewith through the shaft gear latch, a lifting gear rack mounted on the panel edge edgewise thereto, a spur lifting gear rotatably mounted on the window frame positioned to engage said lifting rack operatively, intervening idler spur gears rotatably mounted on the window frame positioned to mesh and connect operatively with both the power gear and lifting gear for raising and lowering the window panel within the window frame slides as the power shaft is rotated, a spiral window counterweight spring mounted on said window frame and connected to one of the idler gears in a manner for supporting the window panel weight, an operating gear mounted on the power shaft positioned to engage operatively with the auxiliary operating gear of the pane pivot shaft when the window panel is in its raised position within the window frame, a hand operating crank with hinged arm and cam mounted on the outer end of the power shaft, said arm cam being positioned to engage and displace the power shaft gear latch and disengage the power gear when the hinge crank arm is displaced on its hinge pivot away from the window frame wall.

8. A duplex turning unit adapted for engaging and operating a loosely mounted drive gear and used in combination therewith, comprising a slotted drive shaft having an internally grooved drive gear loosely mounted thereon, positioned with said groove and shaft slot coinciding, a gear latch arm pivotally mounted within said shaft slot capable of engaging the gear groove when ejected from the slotted shaft, a spring member mounted within the shaft slot beneath the gear latch for engaging said latch operatively with the gear groove, a crank hub fixedly mounted on the shaft end and having a movable crank arm hingedly attached thereto, said crank arm being formed with an extended arm cam positioned to engage the outer end of the pivoted latch arm, capable of disengaging same from the drive gear groove as said movab'le crank arm is displaced manually on its supporting hinge.

9. A duplex ventilation window, comprising an open window panel slidably mounted within suitable support window frame slides, a free window pane pivotally mounted within said window panel opening by attached pivot and pivot shaft means, said pivot shaft having an auxiliary operating gear mounted thereon, a manually operated power shaft with drive gear rotatably mounted on the supporting window frame adjacent said window panel, rotatable geared operating mechanism mounted on said window frame and connected to said window panel, said geared operating mechanism being connected to and actuated by said power drive gear in a manner for raising and lowering said window panel within the window frame slides as the power shaft is rotated, an operating gear mounted on said power shaft positioned to engage and mesh operatively with said auxiliary operating gear of the free pane pivot shaft, when said window panel is raised to its extreme closed position.

10. A duplex ventilation window, comprising an open window panel slidably mounted within suitable support window frame slides, a free Window pane pivotally mounted within said Window panel opening by attached pivot and pivot shaft means, said pivot shaft having an auxiliary operating gear and retarding means mounted thereon, a power shaft with drive gear having a manual operating crank rotatably mounted on the supporting window frame adjacent said window panel, continuous rotatable geared panel operating mechanism mounted on said window frame, connected to and actuated by said power shaft drive gear, said operating mechanism also being connected with the window panel in a manner for raising and lowering same Within the supporting window slides as said power shaft is rotated, an operating gear mounted on the power shaft positioned to engage and mesh operatively with the auxiliary operating gear of the free window pane operating shaft when said panel is raised to its extreme closed position within the supporting window frame slides, and means formed thereon for disconnecting the panel operating mechanism from the power shaft when the pane operating gears are closed operatively together.

11. A duplex ventilation window, comprising an open window panel slidably mounted within suitable support window frame slides, a free window pane pivotally mounted within said window panel opening by attached pivot and pivot shaft means, said pivot shaft having an auxiliary operating gear with spring actuated retarding collar mounted thereon, a power shaft with drive gear mounted thereon rotatably mounted within the window frame adjacent the window panel, said power shaft having an operating crank on one end thereof, a lifting mechanism drive shaft with gear attached rotatably mounted on the window frame, positioned with said gear meshed operatively with the drive gear of said power shaft, panel lifting means mounted on the window panel frame and engaged operatively with said lifting mechanism drive shaft in a manner capable of raising and lowering said window panel within its supporting slides as said power shaft is rotated, said lifting mechanism being formed to become disengaged from the power shaft when said window panel is raised to its closed position, an operating gear mounted on said power shaft positioned to engage and mesh operatively with the free pane pivot shaft operating gear when the window panel is raised to its extreme closed position and as said lifting mechanism is disconnected from the connected drive shaft.

12. A duplex ventilation window, comprising an open window panel slidably mounted within suitable support window frame slides, a free window pane pivotally mounted within said window panel opening by attached pivot and pivot shaft means, said pivot shaft having an auxiliary operating gear and shaft retarding unit mounted thereon, a power shaft with drive gear rotatably mounted on said window frame adjacent the window panel, said shaft being provided with a turning crank mounted on one end thereof, a worm lifting shaft with gear attached also rotatably mounted on the window frame parallel to the frame panel slides and with said shaft gear meshed operatively with the drive gear of the power shaft, an operating thimble mounted over said worm shaft and threadably connected thereto, said thimble also being connected to the window panel in a manner capable of raising and lowering same when said worm shaft is rotated, said worm shaft being shouldered at the top end for disengaging the operating thimble when the connected window panel is raised to its extreme closed position, said operating thimble being formed with a thread engaging edge for re-engaging said worm shaft threads when said shaft rotations are reversed, and an operating gear mounted on the power shaft positioned to engage and mesh operatively with the auxiliary operating gear of the free pane pivot shaft when the window is raised to its closed position.

ELMER J. KIRCI-IOFF. 

